Stone



(No Model.) 2 Sheets-Sheet 1.

P. W. JOHNSTONB. BRICK ARCH FOR LOGOMOTIVE FIRE BOXES.

No. 481,232. Patented Aug. 23,1892.

(No Model.) 2 Sheets-Sheet 2.

' F. W. JOHNSTONE.

BRICK ARCH FOR LOCOMOTIVE PIRE BOXES.

Patented Aug. 23, 1892.

UNITED STATES PATENT OFFICE,

FRANCIS W. JOI-INSTONE, OF MEXICO, MEXICO.

BRICK ARCH FOR LOCOIVIOTIVE FIRE-BOXES.

SPECIFlCATION forming part of Letters Patent No. 481,232, dated August 23, 1892.

Application filed February 13, 1892, Serial No. 421,404. (No modeLl To all whom t may concern Be it known that I, FRANCIS NV. JOHN- STONE, a citizen of the United States, residing at the city of Mexico, in the Republic of Mexico, have invented a certain new and useful Improvement in Brick Arches for Locomotive Fire-Boxes, of which im provenientthe following is a speciiication.

The object of my invention is to admit of the application of brick arches to locomotive fire-boxes of any of the various constructions in standard practice, in such manner that the arch may be firmly supported when in use without the employment of attachments to the fire-box sheets, and maybe readily and expeditiously inserted and removed, as required, for renewal or repair.

To this end my inventiomgenerally stated, consists in the combination,with a locomotive tire-box, of a transverse girder or support fixed below the mud-ring or bottom bar, a brick arch supported on said girder, and an auxiliary ash-pan located below the firebox and between the girder and the iiuesheet. rlhe improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure l is a vertical longitudinal central section through a locomotive tire-box, illustrating an application of my invention; Fig. 2,ahorizontalsec tion through the same, and Fig. 3 a vertical transverse section through the lower portion of one of the side water-legs and the adjacent portion of the brick arch and supportinggirder.

My invention is herein shown as applied in a locomotive fire-box l of the well-known Belpaire type, to which special construction it will,however,be obvious that it isin no degrec limited. The fire-box is provided at bottom with a suitable grate 2, which extends for the major portion of its length and with an ordinary ash-pan 3 below the grate. A girder or support 4, which is preferably of cast-iron, extends across the bottom of the tire-box in front of the ash-pan -that is to say, at or near its end which is adjacent to the flue-sheet 5said girder being secured at its ends either to the side members of the mud-ring or bottom bar 6 of the tire-box, as shown in Fig. 3, or to the engine-frames when the fire-box is so located relatively thereto as to make such attachmentconvenient or desirable-for example, entirely above the frames, as is frequently the case in recent and present practice. The girder 4 forms the rear wall of a supplemental ash-pan 7, which extends below the forward portion of the firebox to or near the plane of the nue-sheet 5, and is provided at its sides with tight doors or dampers 8. An arch or bridge-wall 9, formed of a series of lire-brick sections, and havingpreferably, arearwardly-inclined upper portion, rest-s upon and' is supported wholly by the girder l,which may be, as shown, provided with lateral flanges on its upper surface to abut against and hold in position the lower sections of the arch 9. The space l() between the arch and the flue-sheet is open at bottom to the supplemental ash-pan 7 and serves the purpose of a combustionchamber in which the combustion of the gaseous products of the ignited fuel on the grate is'perfected before passing into and through the tubes 1l.

It will be seen that the construction above described obviates the necessity of perforating the tire-box sheets for the attachment of the supporting devices ordinarily heretofore employed, and that the brick arch may be readily put in place and removed or repaired, as required. The supplemental ash-pan 7 being practically air-tight, such cinders as may be carried over the top of the arch by the action of the exhaust fall into a space in which they are undisturbed by any upward draft and remain quiescent in the supplemental ash-pan, from which they may be removed at proper intervals through the openings controlled by the side doors or dampers 8. Y

I claim as my invention and desire to secure by Letters Patent- The combination, with a locomotive tirebox, of a transverse gil-der or support fixed below the bottom of the fire-box and independently of the side sheets thereof, as by connections to the mud-ring, and a brick arch built upon and supported by said'girder independently of the fire-box sheets and extending across the'tire-box, substantially as set forth.

FRANCIS W. JOHNSTONE. Witnesses:

F. E. TRAINER, WM. M. EDGAR.

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